1. Technical Field
The following description relates to one or more techniques for a communication device configured to perform communication using a public network and an Internet Protocol (IP) network.
2. Related Art
A communication terminal device has been known, which is connected with an IP (Internet Protocol) network and a public network. The communication terminal device is configured to detect a communication error when making a call to the IP network or the public line network. When detecting a communication error, the communication terminal device analyzes the detected communication error to obtain an analysis result as to whether the detected communication error is a network selection error (i.e., such an error as “Not Found” under which redialing to the same network is ineffective) or an error other than the network selection error (e.g., an error indicating that a party device is busy). Then, the communication terminal automatically determines whether to make redialing to the IP network or the public network based on the analysis result regarding the communication error.